Core Biopsy Please!!

The only way to know for sure would require a core biopsy. This procedure is quite simple to perform in the field and will save significant time with regards to treatment and resolution of clinical signs. The first image was treated unsuccessfully as a "summer sore" with medication that actually worsened the clinical signs. The biopsy results were consistent with Pythiosis and aggressive medial/surgical treatment was instituted. The prognosis for full recovery is not good once there has been significant disruption of the soft tissue structures and in a case that involves the lower pastern/coronary band area. Early diagnosis is key!

The case below was treated as a suspect "summer sore" with minimal improvement. Biopsy results indicated that it in fact it was a case of Habronemiasis that was not responsive to the treatment provided (systemic and topical ivermectin). Habronemiasis or "Summer Sores" is a condition that results from flies depositing larvae within the skin causing a significant allergic reaction. Treatment involves medication to kill any living fly larvae and most importantly medication to suppress the local allergic reaction. Treating with ivermectin systemically and topically is often not enough!! Yet that is how many try to treat this condition! For small lesions, topical treatment with concentrated cortisone can be effective, however, for more aggressive lesions, systemic administration with corticosteroids is necessary. Importantly, systemic treatment with corticosteroids is the treatment you definitely want to avoid if you are dealing with Pythiosis! Hence the importance of a core biopsy.

Equine Strangles

Equine Strangles!!

(Figure 1)

(Figure 2)

The disease process that may cause throat latch swelling AND limb swelling is commonly known as Equine Strangles. This disease is caused by a bacteria known as Streptococcus Equi subspecies Equi. Most commonly it results in enlargement of the lymphnodes within the throat latch area that may narrow the airway of the horse, hence the term "strangles". In severe cases, a temporary tracheotomy is necessary to save the horses life! (Figure 1). These lymph nodes may rupture and drain purulent debris from the outside or from within the guttural pouches (Figure 2). These horses are typically febrile, depressed, and highly contagious! Occasionally, the horse will develop a hyper-immune response known as purpura hemorrhagica. This immune response to the bacteria results in severe swelling of one or multiple limbs (Figure 3)  and can be triggered by the vaccination of a horse that was recently sick with the disease.

(Figure 4)

For more information check out the following links:

http://en.wikipedia.org/wiki/Strangles

http://www.aaep.org/strangles.htm

Mesotherapy 

These small bumps were caused by micro-injections of medication just under the skin, or also known as Mesotherapy. This treatment has been used effectively for over 30 years in humans and horses. The primary objective of this treatment in horses is to block or break the pain cycle associated with chronic back pain. 

Technically, mesotherapy treatment stimulates the mesoderm or middle layer of skin by stimulating the giant fibers present within this layer of skin. Commonly, a combination of lidocain and dexamethasone is injected via multiple extra small needles (30g). These micro-injections result in stimulation of the giant nerve fibers located within this layer of skin that also communicate with major nerve tracts within the spinal chord. These nerve fibers INHIBIT the conduction of pain signals to the brain.

Typically, one or two mesotherapy treatments are applied to a horse's back and often are combined with shockwave treatments. Mesotherapy is used primarly as an aid to alleviate back pain followed by treatment of the primary cause of the back pain/spasm. This typically involves a source of lameness in either the forelimbs or hindlimbs. In addition, osteo-arthritis of the thoraco-lumbar spine and "kissing spines" are causes of chronic back pain. 

The response to mesotherapy is usually within 2-3 days and may last for 3-4 months. 

Asymmetric pelvis

The pictures above are those of a horse with an asymmetric pelvis. Specifically, the left tuber sacrale is lower than the right. Less severe varieties of this problem have been described as "hunters bumps". The appearance of asymmetric tuber sacrale or "hunters bump" is in indication of a pathological problem within the pelvis/sacrum area. In the case above, the gelding suffered a fractured pelvis that was diagnosed via ultrasound. This patient presented for non-weight bearing lameness however many with only mild changes do not present for lameness but rather "poor" performance.

In the image above, the left gluteal region was examined via ultrasound and an irregular margin was noted along the body of the ileum. Note the "step" along the bony margin in the pic below.

Less severe cases involve inflammation within the sacro-iliac joint and/or inflammation of the dorsal sacroiliac ligaments. These areas should be assessed for evidence of inflammation and treatment may include shockwave treatment, mesotherapy, and/or sacro-iliac joint injections.

Suspensory Break Down!

The suspensory ligament has been significantly stretched and strained, resulting in the "dropped fetlock" conformation seen below. The suspensory ligament (blue structure in drawing below) originates just below the hock in the hind limbs and the carpus in the forelimbs. The ligament splits into a medial (inside) and lateral (outside) suspensory branch. The split occurs approximately half way down the metatarsus. Each suspensory branch inserts on a sesamoid bone at the level of the fetlock and play a role in "suspending" the fetlock. For the fetlock to drop, the suspensory branch and body have been strained and maybe even ruptured. For definitive diagnosis, an ultrasound exam is performed that will evaluate the entire suspensory ligament. If the process is slow (months to years), it may result in reduced performance and low grade lameness. However, if sudden, significant lameness is associated with the limb or limbs affected. Unfortunately, this is a progressive condition that will ultimately result in retirement of the horse and may be life-threatening. Management of this condition includes reduced exercise, daily ice therapy, corrective shoeing, and daily pain management. This condition carries a poor prognosis for return to work and a guarded prognosis for over-all soundness.

The blue structure depicts the suspensory ligament in the forelimb. Note the upper region is one structure (body) which then splits into two branches.

These are known as "fish tail" shoes and are quite effective in reducing the strain on the suspensory ligaments. For obvious reasons, this type of shoe, with significant heel extension, can only be used in the hind limbs. 

What is that bug?

Blister beetle is his name and death is his game! 


Ingestion of just a few of these insects results in Cantharidin toxicosis. The poison from these beetles results in large scale ulceration of the oral mucosa, esophagus, and stomach. In addition, the horses often are stricken by acute kidney failure, laminitis and death shortly there after, despite significant medical intervention. The beetles live in alfalfa hay and are often transported in bales of hay from the western part of the United States. 


Check out the following website for more details regarding this horrible bug!


http://www.ca.uky.edu/entomology/entfacts/ef102.asp

Poisonous Plants Quiz

The plants in the pictures were:

1- Creeping Night Shade (bottom pic with black berries)
2- Crotalaria "Rattle Box" (top pic with yellow flowers)

Both are quite common in the state of Florida and both are highly toxic to horses. Toxicity due to Crotalaria ingestion is more common and can result in end-stage liver failure. You can purchase a book that has a great description of the most common poisonous plants in the state of Florida @

http://ifasbooks.ifas.ufl.edu/p-510-poisonous-pasture-plants-of-florida.aspx

Shockwave treatment for horses: More than just bowed tendons!

Shock-wave treatment has been used in veterinary medicine for over a decade.  Initially, the primary use was for inflamed tendons and ligaments; however, this modality of treatment is now commonly applied to chronic wounds (Figure 1 and 2), bone fractures (Figure 3), navicular disease, back pain, sacro-iliac (SI) pain, muscle pain/inflammation, osteoarthritis, and chronic foot pain. 

Shock-wave treatment consists of exposing a specific area of interest to acoustic waves of varying intensity. There are different size probes which correspond to the depth of tissue penetration. A more shallow probe is used for tendonitis of the superficial digital flexor tendon and the deepest probe is used for chronic pain within the epaxial musculature of the horse's top line. The number of shock waves and intensity is adjusted depending on the specific area being treated. For most conditions, the area is treated with 3 sessions that are separated by 10-14 days. For chronic wound healing, low energy is applied and the sessions are every 5-7 days. 

Generally speaking, shock-wave therapy has its greatest benefit by enhancing the development of new blood vessels and thus increasing the blood supply to a region of interest. This will increase the quality and quantity of "healing". In addition, shock-wave therapy will provide short term pain relief to the soft tissues that are inflamed. 

It is very important to remember that shock-wave therapy is only 1 part of managing the above mentioned conditions. It does not replace time nor the benefits of medical treatment and corrective shoeing. However, it does improve the "quality" of healing which is evident in the final product. 

Chronic wound over elbow which has stopped
shrinking in size 2 months after initial injury.

Chronic wound after 3 shockwave treatments.
The cross sectional area has decreased by nearly 30%

A chronic exostosis or splint bone fracture is treated with
shockwave treatment to stimulate healing

Horse with heaves....not so fast!

A middle-aged draft gelding presented for a complaint of difficulty breathing for several months duration. The increased respiratory rate began during the late summer months and was presumed to be likely Heaves/COPD. As the ambient temperature cooled during the fall and winter months, the gelding's respiratory efforts remained elevated. He was referred to PHD Veterinary services to confirm the diagnosis of Heaves/COPD. At presentation, the gelding displayed a significant abdominal component during inspiration and expiration. However his lung sounds were relatively normal. The typical crackles and wheezes that are common in horses with Heaves/COPD were not present. The gelding was slightly under weight and the rest of the physical exam was normal. A bronchio-alveolar lavage (BAL) was performed through a bronchoscope. Upon inspection of the larynx, it was noted that there was minimal if any movement of either arytenoid cartilage (Figure 1).     The image below was taken during inspiration when the airway should be at its maximum diameter. Due to the apparent bilateral paralysis, the gelding's airway consisted of a small slit which would be similar to trying to breath through a straw. The BAL procedure was performed and the cytology results were normal which completely ruled Heaves/COPD. 

The figure below is that of a normal larynx during inspiration with functioning arytenoid cartilages. Note the size of the airway compared to the above image. 

                        

The image below is that of a "roarer" in which the left arytenoid cartilage is completely paralyzed and not moving. This type of condition and varying degrees of paralysis are most common in horses. Bilateral paralysis is rare and carries a worse prognosis. The cause of the paralysis is unknown and management of horses with bilateral arytenoid paralysis is limited.  Permanent tracheostomy is a recommended procedure and will allow the horse to return to a normal respiratory rate and comfortable life in the pasture. 

There are many horses with increased respiratory effort during the warm summer months in the Southeastern USA that suffer from Heaves/COPD. A large percentage of these horses are treated empirically with medications and management practices.  However, this case highlights the importance of diagnostic imaging of the airway to help confirm the diagnosis, especially in those horses that are not responding as expected to medical treatment. 

The Benefits of Platelet Rich Plasma (PRP)

Platelet Rich Plasma (PRP) treatment has been used in modern medicine since the 1990s. It was originally used to facilitate wound healing in humans after oral surgery. Platelet-rich plasma is a blood product that has a high concentration of platelets, growth factors and cytokines that enhance healing of bone and soft tissue. 

In human medicine, PRP has been implemented in the treatment of nerve injuries, tendinitis, osteoarthritis, bone repairs, plastic surgery, and oral surgery. In horses, veterinarians are using PRP for the treatment of tendon/ligament injuries and osteoarthritis. 

The following images are from 2 different cases in which treating with PRP made a significant difference in the quality of tendon repair. In the first case, a 6 year old Saddlebred mare presented for acute lameness at a show that was associated with soft tissue swelling over the flexor tendons. Ultrasound of the limb noted significant swelling of the superficial digital flexor tendon (SDF) and a core-like lesion (Figure 1) that appears as a black circular structure within the SDF tendon. This lesion extended 4-5cm in length. These findings were consistent with moderate to severe tendinitis of the SDF tendon.

Figure 1

The tendon was treated with approximately 10cc of PRP product by injecting the core lesion via ultrasound guidance. The area of interest was treated in multiple sites. In addition, the mare was treated with forced rest, daily ice therapy and extra-corporeal shockwave treatment (3X). The tendon was re-ultrasounded 6 weeks post PRP injection (Figure 2). The core-like lesion was filled in and the over-all cross sectional area (CSA) of the tendon was significantly reduced.

Figure 2

The second case was a 14 year old Fresian gelding that presented for a chronic (2-4 months) history of forelimb lameness. The lameness blocked out to the proximal metacarpal region which is just below the carpus (knee). The ultrasound exam of this area noted an enlarged SDF tendon with a CSA that was over 3X the normal size (Figure 3) . In addition, there was evidence of fiber disruption and edema present within the tendon. The area of interest was treated with approximately 10cc of PRP product that was injected at multiple sites. In addition, the gelding was treated with forced rest, ice therapy, and extra-corporeal shockwave treatment.

Figure 3

The SDF tendon was re-ultrasounded 4 weeks after PRP and the CSA of the tendon was greatly reduced (Figure 4). There appeared to be better fiber alignment and the gelding's lameness was greatly improved.

Figure 4

Both of these cases are good examples of the benefits of PRP treatment. However, it is important to note that forced rest and a controlled rehabilitation program are critical components to a successful outcome. Current PRP technology allows for on-site treatment and there are a variety of products available to the veterinarian for the production of PRP. The quality of product is directly correlated to the high concentration of platelets and the low concentration of white cells. More recently, practitioners are using PRP treatments in horses that have arthritis as a healthy alternative to cortisone treatment.